ABSTRACT
Movement disorders are neurologic syndromes in which movement is either excessive (hyperkinesia) or too little (hypokinesia). A general term used for both hyperkinesia and hypokinesia is dyskinesia, which is defined as difficulty with performing voluntary movements. The prototypic hypokinetic movement disorder is Parkinson disease. Other terms used to describe this movement disorder are bradykinesia (slowness of movement) and akinesia (loss of movement). Common hyperkinetic movement disorders include tremor, tics, and restless legs syndrome (see Chapter 9 for restless legs syndrome). The definition of many hypokinetic and hyperkinetic movement disorders and common clinical examples are listed in Table 12.1.
